<?php
/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 *
 * @category   Zend
 * @package    Zend_Pdf
 * @subpackage Actions
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 * @version    $Id: Action.php 16978 2009-07-22 19:59:40Z alexander $
 */

/** Internally used classes */
require_once 'Zend/Pdf/Element.php';


/**
 * PDF name tree representation class
 *
 * @todo implement lazy resource loading so resources will be really loaded at access time
 *
 * @package    Zend_Pdf
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
class Zend_Pdf_NameTree implements ArrayAccess, Iterator, Countable
{
	/**
	 * Elements
	 * Array of name => object tree entries
	 *
	 * @var array
	 */
	protected $_items = array();

	/**
	 * Object constructor
	 *
	 * @param $rootDictionary root of name dictionary
	 */
	public function __construct(Zend_Pdf_Element $rootDictionary)
	{
		if ($rootDictionary->getType() != Zend_Pdf_Element::TYPE_DICTIONARY) {
			require_once 'Zend/Pdf/Exception.php';
			throw new Zend_Pdf_Exception('Name tree root must be a dictionary.');
		}

		$intermediateNodes = array();
		$leafNodes         = array();
		if ($rootDictionary->Kids !== null) {
			$intermediateNodes[] = $rootDictionary;
		} else {
			$leafNodes[] = $rootDictionary;
		}

		while (count($intermediateNodes) != 0) {
			$newIntermediateNodes = array();
			foreach ($intermediateNodes as $node) {
				foreach ($node->Kids->items as $childNode) {
					if ($childNode->Kids !== null) {
						$newIntermediateNodes[] = $childNode;
					} else {
						$leafNodes[] = $childNode;
					}
				}
			}
			$intermediateNodes = $newIntermediateNodes;
		}

		foreach ($leafNodes as $leafNode) {
			$destinationsCount = count($leafNode->Names->items)/2;
			for ($count = 0; $count < $destinationsCount; $count++) {
				$this->_items[$leafNode->Names->items[$count*2]->value] = $leafNode->Names->items[$count*2 + 1];
			}
		}
	}

	public function current()
	{
		return current($this->_items);
	}


	public function next()
	{
		return next($this->_items);
	}


	public function key()
	{
		return key($this->_items);
	}


	public function valid() {
		return current($this->_items)!==false;
	}


	public function rewind()
	{
		reset($this->_items);
	}


	public function offsetExists($offset)
	{
		return array_key_exists($offset, $this->_items);
	}


	public function offsetGet($offset)
	{
		return $this->_items[$offset];
	}


	public function offsetSet($offset, $value)
	{
		if ($offset === null) {
			$this->_items[]        = $value;
		} else {
			$this->_items[$offset] = $value;
		}
	}


	public function offsetUnset($offset)
	{
		unset($this->_items[$offset]);
	}


	public function clear()
	{
		$this->_items = array();
	}

	public function count()
	{
		return count($this->_items);
	}
}
